1. Field of the Invention
This invention relates to an improved stacker for stacking a plurality of flat objects. The improved stacker is suitable for use with a packaging machine such as a shrink wrap packaging machine. The invention also relates to an improved easy open shrink wrap package for a plurality of flat objects.
2. Background of the Invention
Various types of packaging machines have been developed in the past for packaging articles of various shapes and sizes. One very popular type of packaging machine is a shrink wrap packaging machine for producing a shrink wrap package from a heat shrunk shrink wrap packaging film.
Shrink wrap packaging has become an extremely popular method of encapsulating a single or plurality of objects. Shrink wrap packages may be used for either an internal packaging or for an external packaging. Typically, a shrink wrap packaging film is formed into a longitudinally extending horizontal film tube. The lateral edges of the shrink wrap packaging film are established in an overlapping relationship and are secured by a longitudinal extending seal. Typically, the longitudinal extending seal is formed by either a static generator or linear heat seat as should be well-known to those skilled in the art.
A heat seal is formed on a leading end of the horizontal film tube and the object or objects are aligned and inserted into the longitudinally extending horizontal film tube. A heat seal is formed on a trailing end of the horizontal film tube forming a loose package with the object or objects being disposed therein. The loose package containing the objects is then passed through a heat shrinking oven to shrink the shrink wrap packaging film to form the completed heat shrink package.
Although a variety of objects have been packaged with packaging machines, many objects have not been packaged by packaging process due to the shape of the object. The problem of the shape of the object is especially significant in a shrink wrap packaging machine. In the past, objects that do not remain in a stable position during the movement into the longitudinally extending horizontal film tube or during the movement into the heat shrinking oven have not been packaged by the shrink wrap packaging process.
One extremely difficult type of object to package is a plurality of flat objects. A plurality of flat objects present a particular problem because flat objects, when placed on end, have essentially no stability in either a longitudinal or a lateral direction. This problem is further complicated when the flat object is embodied in a disk-shaped object such as hamburger patty or the like.
Although some in the prior art have attempted to provide a shrink wrap packaging machine to solve this problem, a suitable solution has heretofore not been provided by the prior art. Accordingly, the packaging of flat objects, such as hamburger patties, fish patties, rice cakes, potato patties is presently a hand operation. Considering the enormous number of these flat objects sold and consumed each day, such a hand operation significantly adds to the cost of the flat object.
Therefore, it is an object of this invention to provide a machine for stacking a plurality of flat objects comprising a first and a second rotatable starwheel for forming a vertical stack of the flat objects from the plurality of flat objects.
Another object of this invention is to provide a machine for stacking a plurality of flat objects to form a vertical stack of the flat objects from the plurality of flat objects with a second transferred flat object supporting a first transferred flat object.
Another object of this invention is to provide a machine for stacking a plurality of flat objects including counting means for counting a preselected number of the plurality of flat objects to form a preselected vertical stack of the flat objects.
Another object of this invention is to provide a machine for stacking a plurality of flat objects including an input conveyor stop for intermittently terminating the movement of the plurality of flat objects on an input conveyor to the starwheels.
Another object of this invention is to provide an improved shrink wrap packaging machine for packaging a plurality of stackable objects which is capable of aligning flat objects or the like within a shrink wrap packaging film in a stacked relationship.
Another object of this invention is to provide an improved shrink wrap packaging machine for packaging a plurality of stackable objects wherein the machine is capable of counting the number of flat objects to insure uniformity of packaging of the plurality of the flat objects.
Another object of this invention is to provide an improved shrink wrap packaging machine for packaging a plurality of stackable objects which is applicable for shrink wrap packaging of flat objects and the like.
Another object of this invention is to provide an improved shrink wrap packaging machine for packaging a plurality of stackable objects wherein the process time through the heat shrink oven is carefully controlled to insure that frozen items such as hamburger patties, fish patties, rice cakes, potato patties are not overly heated to prevent degenerating the flavor of the product.
Another object of this invention is to provide an improved shrink wrap packaging machine for packaging a plurality of stackable objects which is relatively small in size in comparison to conventional shrink wrap packaging machines.
Another object of this invention is to provide an improved shrink wrap packaging machine for packaging a plurality of stackable objects which is reliable and sanitary for shrink wrap packaging of food products.
Another object of this invention is to provide an improved shrink wrap packaging machine for packaging a plurality of stackable objects which eliminates the need for non-biodegradable wax impregnated cardboard containers.
The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed as being merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention with in the scope of the invention. Accordingly other objects in a full understanding of the invention may be had by referring to the summary of the invention, the detailed description describing the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.